KOM Defender is a free application designed to identify and help remove suspect Strava leaderboard entries. It works for both riding and running activities.

You know the ones - Someone forgets to turn off their Garmin at the end of the ride, throws the bike on top of the car and speeds home, claiming all the Strava KOM's on the way. Or, they go for a ride and mark it as a run activity on Strava.

KOM Defender reviews your rides and runs each week, and checks the top positions on the leaderboard of each of the segments you have covered.
If it finds a suspect entry, it includes it in your weekly email summary and gives you a chance to flag it.